Search Health Studies

Search Results

Low Level Mercury Exposure from Fish Appears Safe During Pregnancy

Seafood is a staple in many traditional diets, but many wonder if the health benefits of fish consumption outweigh the risk of mercury exposure. In a study of 334 infants in Ohio, researchers assessed the neurobehavior of infants and the fish intake and blood mercury levels in mothers and cord blood. The researchers “found minimal evidence of mercury associated detrimental effects” on the infants, with no statistically significant problems related to level of mercury consumption when other lifestyle and dietary factors were controlled for. In fact, the researchers also observed that the infants with higher (but still safe) blood mercury levels had better attention and less need for special handling, suggesting that the benefits of fish consumption may outweigh the risks of low-level mercury exposure.
Neurotoxicology and Teratology. 2016 Feb 12. Pii: S0892-0362(13)30007-1. (Xu Y et al.)

Gluten Free Med Diet Improves Nutrition in Celiac Patients

Maintaining a healthy weight and optimal nutrition can be a struggle for patients with celiac disease, but nutritious diets can help. In a small Italian study, researchers assigned 39 celiac patients to a Mediterranean gluten-free diet. The scientists found that celiac patients following a gluten free diet based on the Mediterranean diet improved their nutritional status, without inducing overweight or obesity. In fact, two of the four malnourished celiac patients were able to reach a healthy BMI, without becoming overweight or obese.
European Journal of Clinical Nutrition. 2016 Jan;70(1):23-7. (Barone M et al.)

Diabetes-Protective Changes to Gut Bacteria after Year on Med Diet

In a small study, Spanish researchers randomly assigned 20 obese men to either a Mediterranean diet, or a low fat, high complex carbohydrate diet (with foods like pasta and cereals) for a year. After a year on their respective diets, both groups saw increases in various gut microbes that are thought to be protective against type 2 diabetes (Roseburia and Parabacteroides  distasonis for Med diet, and Prevotella and Faecalibacterium prausnitzii for low fat, high complex carb diet). The Mediterranean diet group also increased their insulin sensitivity over the year, meaning that their bodies better respond to insulin.
The Journal of Clinical Endocrinology and Metabolism. 2016 Jan;101(1):233-42. (Haro C et al.)

Med Diet Linked with Improved Gut Bacteria

Spanish researchers randomly assigned 239 adults (half with metabolic syndrome, half without) to either a Mediterranean diet, or a low fat, high complex carbohydrate diet (with foods like pasta and cereals) for two years. They found that the Mediterranean diet was able to “restore potentially beneficial members of the gut microbiota,” in patients both with and without metabolic syndrome. The low fat, high complex carbohydrate diet did not result in as many positive changes in gut microbiota as the Mediterranean diet did, although some beneficial changes still occurred.
The Journal of Nutritional Biochemistry. 2016 Jan;27:27-31. (Haro C et al.)

Mediterranean Diet During Pregnancy Linked with Lower Abdominal Obesity in Young Children

To see how diet during pregnancy affects the risk of childhood obesity, researchers analyzed data from over 1,800 mother-child pairs. They found that children were less likely to have a high waist circumference (a measure of abdominal obesity) at age 4 if their mothers were most closely following a Mediterranean diet during pregnancy. However, the researchers found no significant relationship between the expectant mothers’ diet and the subsequent BMI of their children in early childhood.
Pediatric Obesity. 2016 Jan 13. (Fernandez-Barres S) [Epub ahead of print]

Cook Vegetables in Olive Oil for High Antioxidant Content

Cooking vegetables in olive oil is a hallmark of the much-praised Mediterranean diet. To see how different cooking methods affect the antioxidant capacity of vegetables, Mexican researchers compared the antioxidant capacity in potatoes, tomatoes, eggplant, and pumpkin that were raw, deep fried in olive oil, sautéed in olive oil, or boiled. They found that the veggies deep fried in olive oil had the greatest total phenols, followed by the sautéed veggies, then the boiled veggies. The researchers suggest that “deep frying and sautéing conserve and enrich the phenolic composition.” That said, there is no “bad” way to eat vegetables. Rather, this research shows that if it takes a bit of olive oil to make vegetables most delicious to you, all the better.
Food Chemistry. 2015 Dec 1;188-430-8. (Ramirez-Anaya Jdel P et al).

Mediterranean Diet May Prevent Eye Disease

Macular degeneration, an eye condition that can lead to blindness, has no cure or restorative treatment, so prevention is especially important. To study how diet is related to this condition, scientists analyzed the eating patterns of over 2,500 adults, then monitored their eye health for thirteen years. They found that those most closely following the Mediterranean diet (especially those people eating lots of fish and vegetables) were 26% less likely to progress to advanced age-related macular degeneration. Results varied by genetics, with certain gene carriers being more responsive to diet than others.
American Journal of Clinical Nutrition. 2015 Nov;102(5):1196-206. (Merle BM et al.)

Med Diet Improves Blood Sugar Control & Heart Disease Risk Factors in Type 2 Diabetes

Chinese researchers analyzed data from nine different studies with 1178 type 2 diabetes patients being treated with the Mediterranean diet. Compared with those on a control diet (which ranged from their usual diet, to a low fat diet, to a high carb diet, to the American Diabetes Association Diet), those on a Mediterranean diet had improved blood sugar control (hemoglobin A1c, fasting glucose, and fasting insulin), improved BMI and weight loss, lower total cholesterol, triglycerides (a type of fat in the blood), and blood pressure, and improved higher HDL (good) cholesterol.
European Journal of Clinical Nutrition. 2015 Nov;69:1200-1208. (R Huo et al.) [published online 2014 Nov 4]

Mediterranean Diet Linked with Better Brain Structure in Elderly

The Mediterranean diet has long been associated with healthy aging, but emerging research is shedding new light onto why this might be. Researchers analyzed the eating patterns and brain size in 674 elderly (average age 80) adults without dementia in New York City. They found that those most closely following the Mediterranean diet had larger brains (total brain volume, grey matter, and white matter), with an effect similar to 5 years of aging. Of the specific foods studied, eating 3-5 oz fish weekly, and keeping meat intake under 3.5 oz per day, was also linked with larger brain volumes, equivalent to about 3-4 years of aging. These results suggest that a Mediterranean diet, especially one that encourages fish consumption over meat consumption, could promote brain health, as brain atrophy (brain shrinkage) has been linked with cognitive decline.
Neurology. 2015 Oct 21. (Gu Y et al.) [Epub ahead of print.]

Moderate Wine Intake May Improve Cholesterol, Blood Sugar Control in Type 2 Diabetes

Researchers assigned over 200 patients with well controlled type 2 diabetes who don’t normally drink alcohol to eat a Mediterranean diet, and drink 5 oz of either red wine, white wine, or mineral water with dinner for 2 years. The red wine group significantly increased good cholesterol (HDL and apolipoprotein A), and the white wine group significantly decreased fasting blood sugar. “Slow alcohol metabolizers” (based on whether they carry the ADH1B*1 allele) benefited from both red and white wine on their blood sugar control. Both wine groups had improved sleep quality compared with the water group. The researchers concluded that a Mediterranean diet with moderate wine intake “is apparently safe and modestly decreases cardiometabolic risk” in patients with type 2 diabetes.
Annals of Internal Medicine. 2015 Oct 20:163(8):569-79. (Gepner Y et al.)

Replace Butter with Fish, Nuts, Seeds, and Lower Risk of Heart Disease by 25%

Harvard researchers followed over 120,000 adults for 24-30 years, tracking their diet and health records. The scientists found that replacing 5% of daily calories from saturated fat with polyunsaturated fats (found in fish, nuts, seeds, and safflower oil), monounsaturated fats (found in olive oil and canola oil), or whole grains is linked with a 25%, 15%, and 9% lower risk of heart disease, respectively. Additionally, they found that replacing 5% of daily calories from refined grains and added sugars with whole grains or polyunsaturated fats can also significantly reduce heart disease risk, and that replacing saturated fat with refined grains or added sugars does not lower heart disease risk. The researchers concluded, “Our findings provide epidemiological evidence of the current dietary guidelines, which recommend both “replacing saturated fatty acids with monounsaturated and polyunsaturated fatty acids” and “replacing refined grains with whole grains.”” The Mediterranean diet, which spotlights whole grains, fish, olive oil, nuts, and seeds, is the perfect eating plan to put these lessons into practice.
Journal of the American College of Cardiology. 2015 Oct;66(14):1538-48. (Li Y et al.)

Mediterranean and Vegetarian Diets May Benefit Gut Microbiome

Eating a variety of healthy plant foods is one of the best ways to nurture our friendly gut bacteria, and new research suggests that Mediterranean and vegetarian diets may be useful models. Scientists analyzed the eating patterns and gut bacteria of 153 Italian adults. They found that those most closely following a Mediterranean diet or vegetarian/vegan diet had higher levels of short chain fecal acids, a compound associated with many health benefits. On the other hand, those not following a Mediterranean diet had higher levels of urinary trimethylamine oxide, a potential risk factor for heart disease. The researchers also noted that both vegetarian/vegans and those on a Mediterranean diet scored highly on the Healthy Food Diversity Index, meaning that these eating styles could be a useful blueprint for people wanting to incorporate a variety of nutritious foods into their diet.
Gut. 2015 Sept 28. [Epub ahead of print] (De Filippis F et al.)